


Mama Cat

by AstralGato



Category: Undertale (Video Game)
Genre: All the edgy monsters have a soft squishy center and I intend to exploit it, All the monsters are basically huge, Alternate Universe - Underfell, Bara Sans, F/M, Fluff, No romance in the beginning, SO MUCH FLUFF, Self-Insert, Skelebros have a cat, eventually, literal fluff, sans pov, will tag as I go
Language: English
Status: In-Progress
Published: 2018-03-31
Updated: 2018-03-31
Packaged: 2019-04-16 01:35:24
Rating: Mature
Warnings: Graphic Depictions Of Violence, Major Character Death
Chapters: 1
Words: 1,505
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/14153829
Author URL: https://archiveofourown.org/users/AstralGato/pseuds/AstralGato
Summary: The Fallen Child turns on their monster family after living on the surface for two years and Sans gets tasked with caring for Papyrus' cat while everyone searches for the murderous child. Fluffy shenanigans ensue.





	Mama Cat

**Author's Note:**

> This isn't actually my first fanfiction, but it's been forever since I posted anything publically and it was not for this fandom. You guys can thank my boyfriend for being a horrible enabler and encouraging me to write this. I am by no means a professional so, please, let me know of any errors. My dreams actually provided the plot for this one and I'm just building around it as I go. It actually wasn't Doomfanger in my dream, but I couldn't resist the idea once I was awake.
> 
>  
> 
> [For those unaware of Doomfanger click here.](https://www.youtube.com/watch?v=9CtAxRae670)

It had only been two years since monsters had settled onto the surface when the kid had turned on them all. Crimson eyes Sans had seen in countless nightmares staring at him in his waking world. The only difference was that this time, everyone else had seen it too, along with the knife tightly held in their little fist already covered in dust.

The child had chosen to murder them at what they had decided would be the annual get together of the barrier's destruction. Toriel would be their only victim this time, her distressed cry alerting the others in the home. A manic giggle was all the child had managed to utter as they emerged from the kitchen before Undyne summoned countless spears and drowned him out with a roar. Asgore immediately flew into a rage at the sight of his former mate's dust. The kid had severely miscalculated this timeline as everyone summoned attacks, minus Alphys who hid behind Mettaton. No one could remember how long the chaos had lasted and no one cared how much damage was done to Toriel's home, but the brat had turned tail and ran the moment they realized they would not succeed in dusting them all today. They had barely managed to dodge the barrage of fire, spears, bones and bombs hurtling their way, but when the attacks had burnt a child sized hole in a wall they saw their opportunity and took it. Undyne and Papyrus giving chase until they had lost them in the nearby park.

Undyne furiously vowed revenge and was busily rounding up the Snowdin Guard Dogs to track down the child while Papyrus was eerily silent as he accompanied her. Asgore decided to immediately alert the human police to what had transpired whether they would be useful or not. Every monster could still count on one hand how many humans they trusted since coming to the surface. Mettaton left to run an emergency broadcast to warn any monster on the surface that they had been betrayed and to beware of the crimson eyed child that was now loose. Alphys ran home to her own lab promising to find a way to protect everyone from the child or at least find them. Sans, well Sans did the one thing he had neglected to do while underground, he patrolled their neighborhood looking for a sign that the kid was still there.

Sans had been suspicious of the child since the last few timelines he could recall before the current one were nothing but memories of dust covering everything and a pain he could never forget. The pain of loss, loss of a loved one. While he was grateful that his brother and most of his closest friends had survived this time around he would never be able to tell anyone how much losing Toriel had hurt him. When her madness was at its worst she would still find time on her better days to tell jokes through the ruins door with him. It was one of the few things that kept him sane in the violence of the Undergound. She only got closer to Sans when they got to the surface. Always stopping by with pie and even helping to teach Papyrus how to properly make lasagna. He had forgotten himself and hugged her that day. He didn't think his blush would ever go away, his only consolation was the equally rosy tinge on Toriel's fur the rest of the night. He played nice with the kid only because of her. He had even been working up the courage to ask her out.

He couldn't really say he was surprised with how things turned out, but he was surprised that the kid hadn't immediately reset. It was their solution for everything. Died to Jerry, reset. Lost their stupid stick, reset. Smashed their toe on a rock hidden in the snow, reset. Sans had stopped keeping count of how many resets he noticed. It was maddening enough knowing there was a potentially murderous child roaming the already murderous underground with control over specific points in time. This time around though the kid had done everything to befriend everyone. Sans' apathy toward the universe only allowed him to be suspicious for so long, but whenever the kid was near him or Papyrus he couldn't help but keep a socket peeled for anything suspicious. The kid was also twitchy this time around. A nervous energy had surrounded them since emerging from the ruins and hadn't left until a week or so ago. The few notes he had dared to keep for himself about the timelines had always described the child as neutral faced, but helpful or a painfully smiling face that still somehow came off as cold and eerie. 

The patrol kept Sans' mind from wandering into darker thoughts. He gazed at the monster owned businesses which were all closed thanks to Undyne, Papyrus and the dogs warning everyone they could of the threat. He had mindlessly wandered to Grillby's new bar, but it too was closed. He couldn't see a trace of the kid and even his attempts to sense their tainted soul gave him nothing. Sans' steps picked up as his frustration grew, his eye a constant red glow as he fruitlessly searched for the kid. He was about to take out his frustrations on a helpless tree when his phone went off. He growled as he fished it out of his pocket only to find a text from Papyrus.

 **baby bro boss:** SANS! I WILL NOT REST UNTIL I CAN FIND THE EVIL HUMAN SO THE RESPONSIBILITY OF FEEDING DOOMFANGER FALLS TO YOU UNTIL I RETURN! 

_\- y've gotta be kidding me boss. I f'kin forgot about the stupid cat ya found. -_

**baby bro boss:** HER FOOD IS IN THE PANTRY BY THE REFRIGERATOR AND SHE REQUIRES TWO CANS A DAY. ONCE IN THE MORNING AND THEN AGAIN IN THE EVENING.

"fuck."

 **baby bro boss:** ALSO, DO NOT FORGET TO GIVE HER FRESH WATER EVERY DAY! SHE IS STILL GROWING AND NEEDS PROPER CARE!

 _\- pretty sure tha cat was an adult when we found 'er. -_ Sans heaved out a sigh. He knew this meant that Undyne and Papyrus would basically keep searching for the kid until they found them or until they collapsed from sheer exhaustion. 

"fffuuuuuuuck."

The phone began to ring and Sans had nearly dropped it from the surprise. It was Papyrus.

"shit." Sans answered the call and held the phone away from his skull in preparation for his brothers majestic speaking voice.

"SANS! DID YOU GET MY TEXTS! YOU DID NOT REPLY SO DESPITE HOW BUSY WE ARE I DECIDED TO CALL TO MAKE SURE YOU GOT THEM!"

"ye boss. i got 'em."

"EXCELLENT! DOOMFANGER IS VERY SELF SUFFICIENT, BUT ALAS SHE CANNOT OPEN THE CANS AS SHE LACKS THE DEXTERITY IN HER LITTLE PAWS."

"s'cause she's a damn cat boss."

"SANS! I WILL NOT ALLOW YOU TO SPEAK ILL OF DOOMFANGER! SHE IS FAMILY AND AS SUCH DESERVES RESPECT!"

"still jus' a cat boss." Sans rolled his eyes.

"A CAT THAT DESERVES RESPECT! I WILL KNOW IF YOU HAVE BEEN TAKING PROPER CARE OF HER WHEN I RETURN. I KNOW EXACTLY HOW MUCH FOOD SHE HAS LEFT. SHE WILL ALSO NOT NEGLECT TO LET YOU KNOW SHE IS HUNGRY. SHE IS VERY PUNCTUAL AND QUITE PERSUASIVE."

"k, boss. issat all?" Sans doubted the puffball they had found would be anything but a pushover, but he'd humor his brother.

"YOU MUST ALSO TAKE PROPER CARE OF YOURSELF AS WELL! I WILL NOT BE THERE TO SUPERVISE YOUR FOOD INTAKE AND WHETHER OR NOT YOU GET ENOUGH SLEEP, BUT YOU MUST BE CAREFUL! WITH THE HUMAN LOOSE YOU WILL NEED ALL YOUR STRENGTH SHOULD THEY TRY TO AMBUSH YOU! LOCK ALL THE DOORS AND WINDOWS, CHECK BOTH WAYS WHEN CROSSING THE STREET-"

"okay! okay, boss! I got it. ya don't gotta worry 'bout me or doomfanger. worry 'bout yerself l'right."

"VERY WELL SANS. I WILL DO MY BEST AND WILL EXPECT YOU TO DO YOURS AS WELL. I WILL CALL TOMORROW WHEN I HAVE TIME TO KEEP YOU UP TO SPEED WITH OUR PROGRESS."

"thanks boss. love ya baby bro." Sans couldn't help the smirk that spread across his skull.

"LOVEYOUTOOBIGBROTHERGOODBYE!" frantic clattering sounds against the phone before the call ends. Sans let out a low chuckle over his brother's embarassment. Their relationship had gotten much better since they'd been on the surface, but blatant emotional displays like just saying you care were still difficult for Papyrus. It was adorable.

Sans decided to just teleport home. He flicked on the light in the kitchen as soon as he appeared and suddenly heard a soft padding sound. Doomfanger trotted right up to him and let loose the loudest yowls he had ever heard. She then proceeded to rub against his legs, making a fluffy figure eight as she continued yowling incessantly. Sans ran his hand across his skull.

What was his life right now?

**Author's Note:**

> Papyrus is the best edgy baby bro.
> 
> It starts...I hope you guys enjoy this as much as I did writing it.


End file.
